Three-dimensional printer build material augers

ABSTRACT

A three-dimensional printing system may include a three-dimensional printer. The three-dimensional printer may include a station to receive and rotate a build material container having an axial port, an auger and at least one at least one actuator to move at least one of the build material container and the auger relative to one another to position the auger through the axial port into the build material container.

BACKGROUND

Three-dimensional (3D) printing may produce a 3D object by adding successive layers of build material, such as a powder, to a build platform, and selectively solidifying portions of each layer under computer control to produce a 3D object. The build material may be powder, or powder-like material, including metal, plastic, ceramic, composite material, and other print powders. In some examples, the powder may be formed from, or may include, short fibers that may, for example, have been cut into short lengths from long strands or threads of material. The objects form can be various shapes and geometries, and may be produced using a model, such as a 3D model or other electronic data source. The fabrication may involve laser melting, laser centering, heat centering, electron-beam melting, thermal fusion and the like. The model and automated control may facilitate the layered manufacturing and additive fabrication. The three-dimensional printed objects may be prototypes, intermediate parts and assemblies, as well as end-use products. Product applications may include aerospace ports, machine parts, medical parts, automobile parts, fashion products and other applications.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view schematically illustrating portions of an example 3D printing system.

FIG. 2 is a side view schematically illustrating the 3D printing system of FIG. 1 with an example auger of an example 3D printer partially inserted into an example build material container.

FIG. 3 is a side view schematically illustrating the 3D printing system of FIG. 1 with the example auger fully inserted into the example build material container.

FIG. 4 is a flow diagram of an example 3D printing method.

FIG. 5 is a flow diagram of an example 3D printing method.

FIG. 6 is a side view of portions of an example 3D printing system.

FIG. 7 is a side view of portions of the example 3D printing system of FIG. 6 with an example auger partially inserted into an example build material container.

FIG. 8 is a sectional view of portions of an example 3D printing system.

FIG. 9 is a sectional view of the example 3D printing system of FIG. 8 illustrating removal of an example cap from an example build material container.

FIG. 10 is a sectional view of the example 3D printing system of FIG. 8 illustrating positioning of an example auger into the example build material container.

FIG. 11 is a perspective view of an example actuator for positioning an example auger with respect to an example build material container.

FIG. 12 is a sectional view of the example actuator of FIG. 11 mounted to an example auger for insertion into an example build material container.

FIG. 13A is a sectional view of an example build material container with an inserted auger.

FIG. 13B is an enlarged fragmentary sectional view of the build material container of FIG. 13A.

Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. The figures are not necessarily to scale, and the size of some parts may be exaggerated to more clearly illustrate the example shown. Moreover, the drawings provide examples and/or implementations consistent with the description; however, the description is not limited to the examples and/or implementations provided in the drawings.

DETAILED DESCRIPTION OF EXAMPLES

Disclosed herein are example 3D (3D) printing systems, 3D printers, and 3D printing methods that may facilitate the supply of building material to a 3D printer in a less complex, more reliable and more efficient manner. The example 3D printing systems, 3D printers and 3D printing methods facilitate efficient extraction of build material from a relatively simple and low cost build material container. The example 3D printing systems, 3D printers and 3D printing methods facilitate a more automated process for the removal of build material from an interchangeable and replaceable build material container. Likewise, the example 3D printing systems, 3D printers and 3D printing methods may additionally or alternatively facilitate the efficient input of build material from a 3D printer into build material container, such as where build material as being recovered and/or recycled.

The disclosed 3D printing systems, 3D printers and 3D printing methods utilize an auger, also referred to as an Archimedes screw, which is removably insertable into an axial port of a build material container which is to be rotated about its longitudinal axis. The auger rotates with the build material container to remove build material from the build material container. In such implementations, the build material container does not itself include any Archimedes screw or auger movable through its axial port, reducing the cost and complexity of the build material container. In some implementations, the build material container may include a seal across the axial port which is to be broken by the auger during insertion of the auger through the axial port. In some implementations, the build material container may additionally include an inner surface having helical raised portions that guide build material towards the axial port during rotation of the build material container.

The disclosed 3D printing systems, 3D printers and 3D printing methods position the auger relative to the build material container and insert the auger through the axial port into the build material container using the 3D printer itself. In such implementations, the 3D printer may include at least one actuator that moves an attached auger relative to the build material container and at least partially through the axial port of the build material container. In other implementations, the 3D printer may include at least one actuator that moves a build material container relative to the auger to position the auger through the axial port of the build material container.

In one implementation, the at least one actuator rotates the auger during insertion of the auger through the axial port. In one implementation, the at least one actuator partially releases the auger once at least partially inserted into the build material container such that the auger may rotate relative to the at least one actuator and in unison with rotation of the build material container. In another implementation, the least one actuator rotates the auger in the same direction as the direction in which the build material container is rotated during the discharge of material from or the input of build material into the container. In another implementation, the least one actuator rotates the auger in the same direction and at the same speed as a direction and speed at which the build material is rotated during the discharge of material from or the input of build material into the container such that the build material container and the auger rotating unison. In yet another implementation, the build material container is rotated relative to the auger as the auger is being inserted into the build material container.

In some implementations, the axial port is sealed by a removable cover or cap. In such an implementation, the actuator of the printer may grip the cover or cap and remove the cover or cap. In one implementation, the cover or cap may cover a seal, such as a thin puncturable film, which is exposed upon removal of the cap. In one implementation, the auger has a pointed end that punctures or breaks the seal prior art during insertion through the axial port into a previously un-accessed or virgin build material container. In other implementations, the cover or cap may be omitted, wherein the seal retains build material within the container until accessed.

In the example illustrated, the 3D printing systems, 3D printers and 3D printing methods utilize a build material as provided by a build material container. The build material may be a dry, or substantially dry, powder. In one implementation, the build material may have an average volume-based cross-sectional particle diameter sized of between about five and about 400 μm, between about 10 and about 200 μm, between about 15 and about 120 μm or between about 20 and about 70 μm. Other examples of suitable, average volume-based particle diameter ranges include about 5 to about 70 μm, or about 5 to about 35 μm. For purposes of this disclosure, a volume-based particle size is a size of a sphere is the same volume as a powder particle. Average particle size may indicate that most of the volume-based particle sizes in the container are of the mentioned size or size range. However, the build material may include particles or diameters outside the mentioned range. For example, the particle size may be chosen to facilitate pivoting build material layers having thicknesses of between about 10 and about 500 μm, or between about 10 and about 200 μm, or between about 15 and about 150 μm. One example of a manufacturing system may be pre-set to distribute powdered material layers of about 80 μm using build material container that include build material having an average volume-based particle diameters of between about 40 and about 60 μm. One example of a manufacturing system may be pre-set to distribute powdered material layers of about 80 μm using build material containers include the build material having average volume-based particle diameters of between about 40 and about 60 μm.

An additive manufacturing apparatus may also be provided or controlled to form particle layers having different layer thicknesses. For example, use of slurries may enable the use of finer diameter powders, 0.5 um-5 um. In such an implementation, the slurry viscosity may be high enough so that the described Archimedes systems would operate. In one implementation, a slurry of particles having a viscosity of at least 1 centipoise (cP) and up to 200 centipoise (cP) may be utilized. In one implementation, the slurry of particles may have a viscosity of at least 20 centipoise and up to 200 centipoise.

In some implementations, the build material may comprise a semi-crystalline thermoplastic material, a metal material, a plastic material, a composite material, a ceramic material, glass material, a resin material or a polymer material or other types of build material the build material may comprise multilayer structures were each particle comprise multiple layers. In some implementations, a center of a build material particle may be a glass bead, having an outer layer comprising a plastic binder to agglomerate with other particles performing the structure. Other materials, such as fibers, we also be utilized to provide different properties such as strength.

The disclosed example build material containers are removably insertable into a supply station of the 3D printer. In some implementations, the build material containers are likewise removably insertable into a recycling station, wherein build material is inserted in or withdrawn from the build material container. In some implementations, build material is both withdrawn from and inserted into the build material container at the same station. In the example illustrated, the supply stations are disposed along a horizontal axis. As used herein, the term “horizontal” refers to the orientation of the station and the build material container being substantially parallel to the surface that the 3D printer is resting upon. This may be within about 5° of parallel to the service, within about 10° of parallel to the surface, or within about 20° of parallel to the surface. The 3D printer may not necessarily be completely level during operation, but may work when placed on uneven surfaces that are within about 5° of level, within about 10° of level or within about 20° of level.

Disclosed herein is an example 3D printing system. The 3D printing system may include a 3D printer having a station to receive and rotate a build material container having an axial port. The printer may further include an auger and at least one actuator to support the auger in axial alignment with the axle input port and to axially move the auger through the axial port into the build material container.

Disclosed herein is an example 3D printing method that may include loading a build material container, having an axial port, into a station of a 3D printer, moving an auger of the 3D printer through the axial port into the build material container and rotating the build material container at the station while the auger of the 3D printer is residing within the build material container.

Disclosed herein is an example 3D printing method that may include providing a build material container having an axial port and an inner surface having helical race portions to guide build material within the build material container towards the axial port during rotation in a given direction of the build material container. The method may further include inserting an auger through the axial port of the build material container. In one implementation, insertion of the auger through the axial port may result in the auger breaking a seal across the axial port.

FIG. 1 schematically illustrates portions of an example 3D printing system 20. Printing system 20 comprises a 3D printer 22 which is usable with a build material container 24 (schematically shown in broken lines). Build material container 24 supplies build material to printer 22. Build material container 24 comprises an axial port 26 through which build material may be discharged from container 24 or received by container 24. In some implementations, the axial port may be temporarily sealed until the interior of container 24 is accessed. In one implementation, build material container 24 contains and supplies a powder or powder-like material which is withdrawn by printer 22 for 3D printing. In some implementations, printer 22 may direct build material into container 24, such as when unused build material is being recovered and/or recycled by being directed back into container 24.

Printer 22 selectively withdraws build material from container 24 and utilizes withdrawn build material to carry out 3D printing. In some implementations, depending upon a direction that build material container 24 is rotated, printer 22 may additionally direct build material, such as build material recovered from a 3D printing operation, into build material container 24 through the axial port 26. Printer 22 comprises station 30, auger 34 and at least one actuator 38-1, 38-2 (collectively referred to as the at least one actuator 38).

Station 30 comprises a platform or receiver to receive build material container 24 and to rotate to receive build maintainer 24. In one implementation, station 30 comprises a rotary actuator having at least one interface connected to or in frictional engagement with build material container 24 so as to rotate build material container 24 relative to printer 22. In one implementation, station 24 may comprise a cage into which build material in a 24 is received, wherein a rotary actuator, such as a motor, rotates the cage. In one implementation, the rotary actuator may comprise a motor having at least one disc in contact with circumferential sides of build material container 24, wherein build material 24 is rotated while resting upon at least one bearing surface that facilitates such rotation. In some implementations, station 30 surrounds build material container 24. In other implementations, station 30 underlies build material container 24.

In some implementations, station 30 comprises additional components to interact with build material container 24. For example, in other implementations, station 30 may comprise sensors and actuators to determine the presence of build material container 24 as well as to determine and control the dispensing of build material from the build material container 24. Such sensors may include a weighing device that determines the weight of a build material container 24. Such sensors may sense the speed at which build material container 24 is rotated. In some implementations, such sensors may read a tag, code or other identification associated with build material container 24, wherein such information be provided to printer 22 for controlling the dispensing of build material.

Auger 34 comprises an Archimedes screw having helical vanes extending about a central shaft. Rotation of auger 34 in a first direction moves engaged build material towards printer 22, such as out of build material container 24. Rotation of auger 34 in a second opposite direction moves engaged build material away from printer 22, such as into build material container 24. Auger 34 is cantilevered from and rotatably supported by the at least one actuator 38 for insertion into and withdrawal from build material container 24 when build material container 24 is loaded into or onto station 30.

The at least one actuator 38 comprises at least one actuator that is to move at least one of the build material container and the auger relative to one another to position the auger through the axial port into the build material container. In the example illustrated, actuator 38-1 movably supports auger 34 in axial alignment with axial port 26, wherein the actuator 38-1 extends and retracts towards and away from station 30 to controllably position auger 34 relative to the axial port 26. As shown by FIG. 2, actuator 38-1 may extend, moving auger 34 toward station 30 in the direction indicated by arrow 41 such that auger 34 projects into the interior of build material container 24 while build material container 24 supported at station 30. As shown by FIG. 3, actuator 38-1 may fully extend such that auger 34 is fully located within build material container 24. In some implementations, auger 34 may comprise a substantially imperforate head 42 which may extend across cover and occlude port 26 to close port 26 when auger for is fully positioned within container 24 as shown by FIG. 3. When build material is once again ready to be discharged, actuator 28 may retract in the direction indicated by the broken line arrow 43 (shown in FIG. 3) to partially withdraw auger 34 from container 24.

In one implementation, to facilitate the insertion of auger 34 into the interior of build material container 24 through port 26, actuator 38-1 may additionally rotate auger 34 as auger 34 enters build material container 24 through port 26. The direction of rotation of auger 34 may be controlled depending upon whether build material is to be discharged or loaded into build material container 24. In one implementation, once auger 34 has been positioned or inserted into build material container 24 to a selected extent, the at least one actuator 34 may be actuated so as to at least partially release auger 34 such that auger 34 may rotate relative to the least one actuator 38 and rotate with or in unison with rotation of build material container 24 by station 30.

In another implementation, build material container 24 may additionally or alternatively be rotated by station 30 as auger 34 is being positioned through port 26 and into container 24 to assist in the insertion of auger 34 into container 24. In implementations where station 30 provide such rotation of container 24 during the insertion of auger 34, actuator 38-1 may not rotate auger 34, but merely translate auger 34 as auger 34 is held against rotation.

As shown by broken lines, in some implementations, the least one actuator 38 may additionally or alternatively comprise actuator 38-2. Actuator 38-2 moves station 30 and the supported build material container 24 relative to auger 24, towards and away from auger 34 so as to position auger 34 through port 26 into build material container 24. For example, in one implementation, actuator 38-2 may move station 30 and the received build material container 24 in the directions indicated by arrows 45 towards or away from auger 34. In some implementations, station 30 is supported by actuator 38-2. In other implementations, station 30 may be movably supported by rollers, roller bearings, a belt, a track or low friction surface, wherein the at least one actuator 38-2 pushes or pulls station 30 relative to auger 34. In some implementations, the at least one actuator 38 may comprise both of actuators 38-1 and 38-2 which cooperate to control the positioning of auger 34 relative to port 36 and the interior of container 24.

Once auger 34 has been a probably positioned within the interior of container 24, station 30 may rotate container 24 (and auger 34). Such rotation results in build material either being discharged from container 24 or being loaded into container 24, from printer 22, depending upon the direction of rotation. Because auger 34 is supported by printer 22 and controllably positioned into and withdrawn from container 24 by printer 22, build material container 24 may be fabricated, filled with build material and sealed for delivery without an internal auger extending through the discharge port or provided in the discharge port. As a result, build material container 24 may be less complex and less expensive. At the same time, auger 34 may be reused with multiple different build material containers, further reducing cost.

In some implementations, auger 34 may be removably mounted to printer 22. In such implementations, different augers 34 may be exchanged on printer 22. Such different augers may be made from different materials, may have different geometries, may have different sizes or may have different pitches. As a result, different augers may be removably mounted to printer 22 to accommodate different printer demands for build material, different rate at which build material is to be supplied or replenished, different build material containers or different build materials or build material properties. In other implementations, printer 24 may provide with a single type of auger.

FIG. 4 is a flow diagram of an example 3D printing method 100 for withdrawing build material from a build material container and/or for loading recovered or recycled build material into a build material container. Method 100 facilitates use of lower-cost and less complex build material containers and the precise controlled dispensing or loading of build material. Although method 100 is described in the context of being carried out by printing system 20, it should be appreciated that method 100 may likewise be carried out with any of the printing systems or 3D printers described hereafter, or with similar 3D printing systems.

As indicated by block 104, a build material container, such as build material container 24, is loaded into a station of a 3D printer. The build material container has an axial port, substantially centered along a rotational axis of the build material container and through which build material may be discharged.

As indicated by block 108, an auger, such as auger 34, is positioned through the axial port into the build material container. In one implementation, the auger itself is moved relative to the build container to position the auger through the axial port. In another implementation, the auger is stationary as the build material container is moved towards the auger such that the auger is positioned through the axial port into the build material container. In yet another implementation, both the auger and the build material container are moved towards one another to position the auger through the axial port and into the build material container. In one implementation, the auger itself is rotated as it is being positioned through the axial port and into the build material container. In another implementation, the build material container is rotated as the auger is being positioned through the axial port and into the build material container. In yet other implementations, neither the build material container nor the auger are rotated during positioning of the auger through the axial port of the build material container.

As indicated by block 112, the build material container is rotated with the station while the auger of the 3D printer is residing within the build material container. In one implementation, the build material container is rotated with rotation of the auger such as the build material container and the auger in unison. In one implementation, the build material container and the auger may be rotated in a first direction, resulting in build material being discharged from the interior of the build material container. In another implementation, the build material container and the auger may be rotated in a second opposite direction, resulting in build material being loaded into interior the build material container from the printer or another source.

FIG. 5 is a flow diagram of an example 3D printing method 200 for withdrawing build material from a build material container and/or for loading recovered or recycled build material into a build material container. Method 200 facilitates use of lower-cost and less complex build material containers and the precise controlled dispensing or loading of build material. As indicated by block 204, a build material container having an axial port and an inner surface having helical raised portions, such as helical ribs, vanes or ridges, to guide build material within the build material container towards the axial port during rotation of the build material container is provided. In one implementation, the outer surface of the build material container comprises corresponding outer surface usually depressed portions corresponding to the helical raised portions. In another implementation, the outer surface of the build material container has other surface profiles, wherein the inner surface is provided with the helical raised portions.

As indicated by block 208, an auger is inserted through the axial port of the build material container. In one implementation, the build material container may include a seal across the axial port, wherein insertion of the auger through the axial port includes breaking of the seal or puncturing of the seal with the auger. In one implementation, the auger is manually inserted through the axial port of the build material container prior to the discharge of build material from or the loading of build material into the build material container. In another implementation, the auger is supported by a 3D printer that positions the auger through the axial port and into the build material container. For example, one implementation, the printer may move the auger or translate the auger towards the build material container until the auger has been moved through the axial port and into the build material container. In another implementation, the printer may move the build material container towards the auger, which is stationary along its axis, until the auger has been moved through the axial port into the build material container. In yet another implementation, the printer moves both the build material container and the auger towards one another until the auger has been moved or position through the axial port and into the build material container. In some implementations, one or both of the auger and the build material container may be rotated as the auger is positioned through the axial port and into the build material container.

FIGS. 6 and 7 illustrate an example implementation of method 200 being carried out with respect to an example 3D printing system 300. Printing system 300 comprises a 3D printer 322 and build material container 324. Three-dimensional printer 322, schematically shown, is similar to 3D printer 22 described above except that 3D printer 322 is specifically illustrated as comprising a station 330 having a rotary actuator 332. Those remaining components of printer 322 which correspond to components of printer 22 are numbered similarly.

In the example illustrated, station 330 is to underlie a receiver loaded build material container 324. Although not illustrated, in some implementations, station 330 may additionally comprise a cage into which the build material container 324 may be loaded. Rotary actuator 332 comprise an actuator which engages an exterior of build material container 324 and which applies torque to build material container 324 so as to rotate the loaded build material container 324. In one implementation, rotary actuator 332 may comprise a motor having a rubber or rubber-like discs or wheels which frictionally contact cylindrical portions of the exterior of build material container 324 such that rotation of the discs or wheels results in rotation of build material container 324. In other implementations, rotary actuator 332 may grip or engage and axial shaft projecting from build material container 324, wherein the rotary actuator 302 applies torque to the shaft to rotate the loaded build material container 324 about its longitudinal axis. In other implementations, rotary actuator 332 may comprise other mechanisms for rotationally driving build material container 324 about its axis 333.

Build material container 324 comprises a generally cylindrical container for containing the 3D printing build material 352. Printing build material 352 may be a dry, or substantially dry, powder. In one implementation, the build material 352 may have an average volume-based cross-sectional particle diameter sized of between about five and about 400 μm, between about 10 and about 200 μm, between about 15 and about 120 μm or between about 20 and about 70 μm. Other examples of suitable, average volume-based particle diameter ranges include about five to about 70 μm, or about five to about 35 μm. However, the build material may include particles or diameters outside the mentioned range. For example, the particle size may be chosen to facilitate pivoting build material layers having thicknesses of between about 10 and about 500 μm, or between about 10 and about 200 μm, or between about 15 and about 150 μm. One example of a manufacturing system may be pre-set to distribute powdered material layers of about 80 μm using build material container that include build material having an average volume-based particle diameters of between about 40 and about 60 μm. One example of a manufacturing system may be pre-set to distribute powdered material layers of about 80 μm using build material containers include the build material having average volume-based particle diameters of between about 40 and about 60 μm. An additive manufacturing apparatus may also be provided or controlled to form particle layers having different layer thicknesses.

An additive manufacturing apparatus may also be provided or controlled to form particle layers having different layer thicknesses. For example, use of slurries may enable the use of finer diameter powders, 0.5 um-5 um. In such an implementation, the slurry viscosity may be high enough so that the described Archimedes systems would operate. In one implementation, a slurry of particles having a viscosity of at least 1 centipoise (cP) and up to 200 centipoise (cP) may be utilized. In one implementation, the slurry of particles may have a viscosity of at least 20 centipoise and up to 200 centipoise.

In some implementations, the build material 352 may comprise a semi-crystalline thermoplastic material, a metal material, a plastic material, a composite material, a ceramic material, glass material, a resin material or a polymer material or other types of build material the build material may comprise multilayer structures were each particle comprise multiple layers. In some implementations, a center of a build material particle may be a glass bead, having an outer layer comprising a plastic binder to agglomerate with other particles performing the structure. Other materials, such as fibers, we also be utilized to provide different properties such as strength.

As shown by those portions of build material container 324 which are broken away, build material container 324 comprises an axial port 326 which is covered or sealed by a seal 328 and an interior 350 which comprises helical raised portions 352 along the inner surface of interior 350. In one implementation, the seal 328 may comprise a puncturable film or membrane. As further shown by FIG. 6, in the example illustrated, container 324 has exterior helical grooves or depressed portions 354 which correspond to the interior helical raised portions 352. In other implementations, the exterior surface of dictator 324 may omit such depressed portions 354. In the example illustrated, container 324 further comprises a handle 360 to facilitate manual manipulation of container 324.

In one implementation, build material container 324 may be formed from a polymer or plastic material. In one implementation, build material container 324 may form from other materials. In one implementation, build material container 324 may be formed by a blow molding process. In yet other implementations, build material container 324 may be formed by other processes. In each of such implementations, the build material 370 is sealed within the interior 350 of build material container 324 without the provision of an auger as part of the build material container 324. As a result, build material container 324 is less complex and less costly.

As shown by FIG. 7, as part of carrying out method 200, build material container 324 is loaded onto station 330 of printer 322 with the axial port 326 in substantial alignment with auger 34. Thereafter, auger 34 is inserted through the axial port of the build material container 324. In the example illustrated, actuator 38-1 extends to move auger 34 so as to pierce a seal of the container. In the example illustrated, actuator 30-1 extends such that auger 34 punctures the seal 328 as it is moved through axial port 326 into the interior 350 of build material container 324. In one implementation, during such insertion, auger 34 is rotated. In another implementation, auger 34 is not rotating while being translated, wherein rotary actuator 332 rotates build material container 324 during the insertion of auger 34 into the interior 350 of container 324.

In yet other implementations, actuator 38-1 may be omitted and auger 34 may be held stationary along axis 333 as a separate actuator, such as actuator 38-2 (shown and described with respect to FIGS. 1-3), moves container 324 towards auger 34 until auger 34 is positioned to a selected wheel 382 may be withdrawn from the helical into the interior 350 of container 324. In one implementation, rotary actuator 332 may additionally comprise a linear actuator moving container 324 along axis 333 towards auger 34.

In one implementation, rotary actuator 332 may include a motor 380 that controllably rotates a disk or wheel 382 that projects into the external helical grooves or depressions 354, wherein rotation of the disk or wheel 382 not only rotates container 324 but axially moves container 324 along axis 333 towards auger 34 until auger 34 has pierced the container and is projecting into the interior 350. Upon auger 34 extending into interior 350 by a selected extent, the wheel 382 may be withdrawn from the helical groove 354 and positioned on the clinical surface between the grooves such that rotation of the wheel 382 continues to rotate the container 324 without axial movement of the container 324. In yet other implementations, upon auger 34 extending into interior 350 by a by selected extent, the wheel 382 may be withdrawn from the helical groove 354 and a separate wheel 382 that is engagement with exterior surfaces of container 324, between such grooves 354, may be rotated to rotate container 324 without axial movement of container 324, to assist in directing build material 352 towards port 326, where rotation of auger 34 with the rotation of container 324 further withdraws build material 352 through port 326 and into conduits of printer 322 for use in a 3D printing process. Rotation of container 324 and auger 34 in a reverse direction may likewise facilitate the loading of container 324 with build material, such as with build material recovered from a 3D printing process carried out by printer 322.

FIGS. 8-10 illustrate portions of an example 3D printing system 400. Printing system 400 comprises 3D printer 422 and build material container 424. Build material container 424 is similar to build material container 324 described above. Like build material container 324, build material container 424 comprises internal helical raised portions 354, such as an internal helical rib or thread that directs build material 352 within build material container 424 towards an axial port 426. In the example illustrated, the axial port 426 of build material container 424 is sealed by a puncturable film or seal 428.

Printer 422 comprises gripper 500, actuator 502, gripper 504, station 530, rotary actuator 532, auger 534 and actuator 538. Gripper 500 comprises a clamping mechanism that is actuatable between open and a closed state, wherein the gripper 500 may grip a cap 427 of build material container 424. Actuator 502 moves gripper 500 between open and closed states. Actuator 502 is further able to rotate gripper 500 about axis 540, is to translate over 500 in the direction indicated by arrows 541 and is to raise and lower gripper 500 in the direction indicated by arrows 544. In one such implementation, actuator 502 comprises robotic multi-axial actuation systems having multiple electric solenoid and/or hydraulic/pneumatic cylinder-piston assemblies.

Station 530 is similar to station 330 described above. Rotary actuator 532 is similar rotary actuator 332 described above. Station 530 and rotary actuator 532 (schematically shown) rotate container 424 (and an inserted auger 534) during the discharge of build material from container 424 or during the loading of recovered and recycled build material into container 424.

Auger 534 is similar to auger 34 described above. Auger 534 comprises a helical screw supported by printer 422 opposite to axial port 426. Auger 534 is carried by actuator 538. Actuator 538 linearly translate auger 534 relative to container 424 while container 44 is supported by station 530. In one implementation, actuator 538 further rotate auger 534 during such insertion into or withdrawal from container 424.

FIGS. 8-10 illustrate an example method for withdrawing build material from container 424. As shown by FIG. 9, actuator 502 positions and actuates gripper 500 so as to engage, grip, remove and withdraw cap 427. As shown by FIG. 9, actuator 502 may position gripper 500 opposite to a cap 427 while in an open state, may actuate gripper 500 to a closed state so as to extend into a detent or groove on the cap 424 to grip the cap 427, may be rotated about axis 540 to unscrew the cap (where the cap is screwed onto container 424), may move away from container 424 with the carried cap 424 and may be withdrawn or swung in an upwards direction, exposing the uncapped container 424 for engagement by auger 534. In other implementations, gripper 500 and actuator 502 may be omitted where the cap 427 is manually removed from container 424 prior to discharging build material from container 424 or where cap 427 is manually positioned on container 424 after the discharge of build material or after the loading of build material into container 424.

As shown by FIG. 10, following the removal of the protective cap 427, actuator 538 linearly translates and pushes auger 534 and its associated auger valve 535 through seal 428, puncturing seal 428 and into the interior of container 424. For ease of illustration, FIGS. 9 and 10 omit force the printer 422 shown in FIG. 8. In one implementation, auger 534 is inserted until a head 542 of auger 534 closes off and seals axial port 426. Thereafter, when build material is to be withdrawn from or directed into the interior of container 424, actuator 538 partially withdraws auger 534. As such point time, rotary actuator 532 (shown in 8) rotates container 424. During such rotation, auger 534 is sufficiently released or loose such that auger 534 may rotate relative to actuator 538 in unison with the rotation of container 424 by rotary actuator 532. Rotation of container 424 and auger 534 in a first direction results in build material being discharged through the valve 535 as indicated by arrow 560. Alternatively, rotation of container 424 and auger 534 in a second opposite direction results in build material, such as recovered or recycled build material being loaded into container 424 through valve 535 as indicated by arrow 561.

Following such withdrawal of build material or loading of build material, cap 427 may be replaced over axial port 426, closing axial port 426. In one implementation, the cap 427 may be manually replaced. In another implementation, cap 427 may be repositioned and remounted by gripper 500 and actuator 502.

FIG. 11 is a perspective view illustrating an example actuator 638 disconnected from a removable and replaceable auger 634 (shown in FIG. 12). FIG. 12 is a sectional view illustrating actuator 638 removably connected to an example auger 634. Auger 634 and actuator 638 may be utilized in any of the above described 3D printing systems. As shown by FIGS. 11 and 12, actuator 638 comprises a pulling mechanism 700 that is openable and closable to engage an attachment point or head 702 of auger 38. In one implementation, the inter-engaging portions of head 702 and pulling mechanism 700 are polygonal or otherwise asymmetric such that rotation of pulling mechanism 700 also results in rotation of auger 634. In such an implementation, a separate rotary actuator rotates pulling mechanism 700 about axis 720 during insertion of auger 634 into the build material container, such as build material container 324 described above.

As shown by FIG. 12, actuator 638 further comprises an actuation mechanism 708, such as a screw tied to a motor or other powered actuator, to move auger valve 634 into a build material container or out of the build material container along the axis 720. In one implementation, the pulling mechanism 700, functioning as a gripper, may partially open losing its grip or hold on head 702 such that head 702 may rotate within the partially opened or expanded pulling mechanism 700 such that auger 634 may rotate in unison with the rotation of the build material container into which the auger 634 is inserted. When fully closed such that head 702 is fully gripped, rotation of pulling mechanism 700 results in rotation of auger 634 such as during insertion of auger 634 into the build material container. As described above, rotary actuator 332 (described above) may alternatively rotate the build material container as the auger 634 is being inserted into the build material container to assist in the insertion of the auger 634 into the build material container. In one implementation, the pulling mechanism 700 is actuatable to a fully open state sufficient to permit head 702 to be withdrawn such that a replacement or different auger may be mounted to actuator 638.

In some implementations, the axial port of the container may be provided with a scoop that moves powder to the auger when the auger is positioned through the port. FIGS. 13A and 13B illustrate portions of an example build material container 824 with the example auger 634 inserted into and through. Build material container 824 may be utilized in any of the above described methods in implementations. For example, build material and 824 may be utilized in place of build material container 24, 3 to 4 or 424 described above. As described above with respect to build material container 324 and 424, build material container 824 may be provided with a removable cap and/or a puncturable seal across its axial port. Build material container 824 is similar to build material container 324 described above except that build material container 824 comprises a scoop 825 about it axial port 826. Like build material container 324, build material container 824 comprises internal helical raised portions 352, such as an internal helical rib or thread that directs build material within build material container 824 towards an axial port 826.

Scoop 825 guides or conveys build material to the auger 634 inserted through port 826. Scoop 825 is arranged around port 826 and has a helical configuration. Scoop 825 comprises a helical floor 900, a surface 902 and a join 904. The helical floor 900 is shaped as a portion of a helical void, truncated in the axial direction and in the radial direction. In one implementation, the axial position of any point of the helical floor 900 with respect to a fixed point varies linearly with the angular position of the point about the axis 333 of build material container 824. In other implementations, the helical floor 900 may not be shaped as a portion of a helicoid.

Join 904 extends between the helical floor 900 and the surface 1227 to form a curve of a narrowing radius. The radial distance of join 904 from axis 333 decreases from a maximum radius at a first angular position to a minimum radius at a second angular position. In one implementation, the join 904 subtends an angle of one full rotation about the axis 3331 that the first angular position is same as the second angular position. In other examples, the join 904 subtends an angle other than one full rotation.

Rotation of build material container 824 rotates scoop 8252 guide or convey printing material between the interior of container 824 and port 826. The rotation of build material container 824 causes scoop 825 to operate as an Archimedes screw to convey build material. When build material container 824 rotates a first direction, the helical floor 900 conveys build material container towards axis 333 and to auger 634. When build material container 824 rotates in a second opposite direction, depending upon the direction of the helix, the helical four 900 conveys build material container away from axis 333 and into the interior of container 824.

Scoop 825 conveys a discrete dose of build material for a given 360-degree rotation of build material container 824. In the example illustrated, the discrete dose is conveyed when build material container 24 undergoes one full three and 60-degree rotation. In other implementations, the discrete dose may be conveyed in response to the build material container 824 being rotated by multiple 360-degree rotations. In yet other implementations, the discrete dose may be conveyed when build material container 824 is rotated by less than a 360-degree rotation. In one implementation, scoop 825 is integrally formed as a single unitary body with the remainder of build material container 824. In another implementation, scoop 825 is fastened, welded, bonded or is affixed to the remainder of build material container 824. In one implementation, scoop 825 is integrally formed as part of an end cap that is joined to the generally cylindrical body of container 84, closing off an axial end of container 824 and providing port 826.

Although the present disclosure has been described with reference to example implementations, workers skilled in the art will recognize that changes may be made in form and detail. For example, although different example implementations may have been described as including features providing one or more benefits, it is contemplated that the described features may be interchanged with one another or alternatively be combined with one another in the described example implementations or in other alternative implementations. Because the technology of the present disclosure is relatively complex, not all changes in the technology are foreseeable. The present disclosure described with reference to the example implementations and set forth in the following claims is manifestly intended to be as broad as possible. For example, unless specifically otherwise noted, the claims reciting a single particular element also encompass a plurality of such particular elements. The terms “first”, “second”, “third” and so on in the claims merely distinguish different elements and, unless otherwise stated, are not to be specifically associated with a particular order or particular numbering of elements in the disclosure. 

What is claimed is:
 1. A three-dimensional printing system comprising: a station to receive and rotate a build material container having an axial port; an auger; and at least one actuator to move at least one of the build material container and the auger relative to one another to position the auger through the axial port into the build material container.
 2. The three-dimensional printing system of claim 1, further comprising a rotary actuator to rotate the auger as the auger is being axially positioned into the build material container.
 3. The three-dimensional printing system of claim 1, wherein the auger has a port closer and wherein at least one actuator is to axially move the auger into the build material container to a position such that the port closer closes the axial port.
 4. The three-dimensional printing system of claim 3, wherein the least one actuator is to axially move the auger partially out of the build material container.
 5. The three-dimensional printing system of claim 1, wherein the at least one actuator is decouplable from the auger such that the auger may rotate in unison with rotation of the build material container by the station.
 6. The three-dimensional printing system of claim 1, wherein the station is to rotate the build material container in a first direction to discharge build material from the container and a second opposite direction to load build material into the container.
 7. The three-dimensional printing system of claim 1, wherein the actuator is to move the auger so as to pierce a seal of the container.
 8. The three-dimensional printing system of claim 1 further comprising the build material container, wherein the build material container comprises an inner surface having helical raised portions to guide build material within the build material container towards the axial port during rotation of the build material container.
 9. The three-dimensional printing system of claim 8, wherein the build material container further comprises a puncturable seal across the axial port, wherein the at least one actuator is to axially move the auger to puncture the seal.
 10. A three-dimensional printing method comprising: loading a build material container, having an axial port, into a station of a three-dimensional printer; positioning an auger of the three-dimensional printer through the axial port and into the build material container; and rotating the build material container with the station while the auger of the three-dimensional printer is positioned
 11. The method of claim 10 further comprising rotating the auger of the three-dimensional printer while moving the auger through the axial port into the build material container.
 12. The method of claim 10 further comprising axially moving the auger three-dimensional printer to a closing position in which a closer of the auger closes the axial port of the build material container
 13. The method of claim 12 further comprising axially moving the auger from the closing position to an access position at which the auger is partially removed from the axial port and partially within the build material container.
 14. A three-dimensional printing method comprising: providing a build material container having an axial port and an inner surface having helical raised portions to guide build material within the build material container towards the axial port during rotation of the build material container; and inserting an auger through the axial port of the build material container.
 15. The three-dimensional printing method of claim 14 further comprising: breaking a puncturable seal of the container with the auger during insertion of the auger through the azial port. 